Jepson eFlora
Key to families | Table of families and genera

Key to Chaenactis

View taxon page for Chaenactis

Jepson Manual glossary definitions can be seen by moving your cursor over words underlined with dots.

1. Perennial herb (biennial) or subshrub, rarely flowering 1st year; inner fruit pappus generally of 10–20 scales in 3–4 ± equal series; leaf blade gland-pitted under hairs; heads discoid (sect. Macrocarphus)

2. Leaves generally cauline (also basal in Chaenactis douglasii); heads not scapose, (1)2–25+ per stem; plants not or scarcely cespitose or matted

3. Perennial herb or biennial, rarely flowering 1st year or slightly woody; proximal hairs cobwebby to tomentose, ± gray, thinning with age; basal leaves generally persistent, largest leaf blades ± elliptic, not flat ..... C. douglasii var. douglasii

3' Generally subshrub; proximal hairs (especially stems) ± felty, ± white, persistent; basal leaves generally 0, largest leaf blades ± deltate, ± flat

4. Longest phyllaries 10–13 mm, outer ± tomentose, not or scarcely glandular; e Peninsular Ranges ..... C. parishii

4' Longest phyllaries 14–18 mm, outer generally glandular-hairy, other hairs 0 or scarce; e Klamath Ranges ..... C. suffrutescens (2)

2' Leaves ± basal; heads ± scapose, 1(3) per stem; plants cespitose to ± matted

5. Outer phyllaries silky-tomentose, nonglandular ..... C. alpigena

5' Outer phyllaries generally glandular-hairy, often also cobwebby to woolly or shaggy-hairy

6. Largest leaf blades ± deltate to ovate, ± flat; 1° lobes generally 2–4(5) pairs, tips ± flat

7. Plant 2–10(12) cm; leaves 2.5–5 cm; longest phyllaries 9–12(14) mm; corolla 5.5–8 mm; longest pappus scales 3–5 mm ..... C. nevadensis

7' Plant (10)25–45(60) cm; leaves 5–10 cm; longest phyllaries 14–18 mm; corolla 8.5–10 mm; longest pappus scales 7–9 mm ..... C. suffrutescens (2)

6' Largest leaf blades ± elliptic or cylindric to ± fusiform, not flat; 1° lobes (4)5–18+ pairs, tips curled and/or twisted

8. Largest leaf blades ± elliptic; 1° lobes (4)5–9(12) pairs, not or scarcely overlapping ..... C. douglasii var. alpina

8' Largest leaf blades cylindric to ± fusiform; 1° lobes (7)10–18+ pairs, ± overlapping ..... C. santolinoides

1' Annual; inner fruit pappus 0, crown-like, or of 4(5) or (7)8 scales in 1 or 2 unequal series, outer << inner; leaf blades (except Chaenactis macrantha) not gland-pitted; heads discoid or radiant

9. Proximal hairs mealy, scaly, or powdery; largest leaf blades generally ± deltate, (2)3–4-pinnately lobed (sect. Acarphaea)

10. Phyllary tips acute or scarcely acuminate, ± flat, ± green; leaf lobe tips ± flat; receptacle epaleate; fruit compressed; pappus 0 or longest scales <= 0.5 mm ..... C. artemisiifolia

10' All or inner phyllary tips long-acuminate, needle-like, ± red; leaf lobe tips ± cylindric; receptacle paleate; fruit not compressed; longest inner fruit pappus scales generally 3–5 mm ..... C. carphoclinia

11. Leaves basal and cauline, longest 1–6(7) cm; petiole slender, flexible, base scarcely enlarged ..... var. carphoclinia

11' Leaves generally basal, longest 7–10 cm; petiole thick, stiff, base strongly enlarged ..... var. peirsonii

9' Proximal hairs cobwebby to woolly or 0; largest leaf blades linear, entire, or ± elliptic (to ovate), 1–2-pinnately lobed (sect. Chaenactis)

12. Corolla white to ± pink or rarely pale yellow; generally in or near Great Basin Floristic Province, D

13. Heads radiant; peduncle distally generally glandular-hairy, or ± glabrous in fruit; outer corollas bilateral, spreading, > inner; inner fruit pappus generally of 4 scales in 1 series

14. Longest pappus 6–8.5 mm, exceeding corolla, tips visible among buds; proximal hairs 0 by flowering time; largest leaf blades entire or 1-pinnately lobed, lobes generally 1–2(5) pairs; outer phyllaries ± glabrous in fruit, tip acute ..... C. fremontii

14' Longest pappus 1.5–6 mm, not exceeding corolla, tips hidden; proximal hairs persisting at least at nodes by flowering time; largest leaf blades generally 1–2-pinnately lobed, 1° lobes 4–8 pairs; outer phyllaries glandular-hairy and/or ± cobwebby in fruit, tip ± obtuse ..... C. stevioides

13' Heads discoid; peduncle nonglandular; outer corollas radial, spreading or not, ± = inner; pappus of (6)8 scales in 2 unequal series, outer << inner

15. Corolla open at night, anthers ± included; inner corollas 9–12(15) mm, 1.8–2.2 × fruit; leaf blades ± gland-pitted under hairs ..... C. macrantha

15' Corolla open during day, anthers exserted; inner corolla 4–10 mm, ± = fruit; leaf blades not gland-pitted

16. Longest phyllaries 10–18 mm, outer nonglandular, glabrous proximally, densely puberulent distally, tip generally recurved, flexible; pappus scales 8 ..... C. xantiana

16' Longest phyllaries 4.5–10(12) mm, outer generally glandular-hairy, hairs otherwise various, uniform, tip erect, stiff; pappus scales generally < 8 (hybrids; see genus note)

12' Corolla bright to dark yellow; generally California Floristic Province ..... C. glabriuscula

17. Inner fruit pappus generally of 7–8 scales in 2 series, outer << inner ..... var. heterocarpha

17' Inner fruit pappus generally of 4 scales in 1 series

18. Proximal hairs tomentose to woolly, ± white; leaves ± basal, persistent ..... var. lanosa

18' Proximal hairs 0 or ± cobwebby, ± gray; leaves basal (withering) and cauline

19. Largest leaf blades generally 2-pinnately lobed, fleshy; stem ± spreading; South Coast, coastal dunes, bluffs ..... var. orcuttiana

19' Largest leaf blades 1(2)-pinnately lobed, scarcely fleshy; stem erect to ascending; inland from coast

20. Longest phyllaries 5–7 mm, 1–2 mm wide, outer ± silky-cobwebby at least medially in fruit, often also ± glandular-hairy; longest pappus 2–4 mm, 0.4–0.7 × corolla ..... var. glabriuscula

20' Longest phyllaries 7–9 mm, 2–3 mm wide, outer becoming glabrous in fruit; longest pappus generally 5–8 mm, ± 0.9(1) × corolla ..... var. megacephala


Citation for the whole project: Jepson Flora Project (eds.) [year] Jepson eFlora, [accessed on month, day, year]
Citation for an individual treatment: [Author of taxon treatment] [year]. [Taxon name] in Jepson Flora Project (eds.) Jepson eFlora, [URL for treatment]. Accessed on [month, day, year].
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